Ever since the invention of the wheel, human beings have transported goods by a vehicle from one location to another. Today, goods are transported by trucks, trains, airplanes and boats as cargo for delivery to virtually any location throughout the world. Particularly for commercial purposes, cargo is usually first loaded into a cargo container before being transported. A typical cargo container associated with trucks is a semi-trailer; a typical cargo container associated with trains is a boxcar; and, a typical cargo container associated with airplanes and boats is a "hold". For a variety of reasons, it is important to stabilize the cargo within the cargo container while it is being transported. During transportation, various movements of the transporting vehicle, such as stops, starts and turns, can cause the cargo within the cargo container to move. Movement of cargo within the cargo container poses several problems. First, two cargo items can collide thereby causing damage thereto. Second, movement of the cargo within the cargo container can damage the cargo container which could potentially render it unusable for further service. Third, moving cargo within the cargo container causes the center of gravity of the cargo container to shift. A significant shift of the center of gravity of the cargo container results in a perilous situation for the driver of the vehicle. For example, a turning vehicle with a significant shift of its center of gravity can rollover causing death and injury to the driver and pedestrians as well as damage to the cargo.
To resolve these problems, various means and devices have been developed to restrain the cargo within the cargo container as it is being transported. One means of restraint requires that the cargo be secured to the upright support walls of the cargo container. Usually, the upright support walls of the container are provided with fixtures so that ropes or straps can be releasably affixed thereto to restrain the cargo to the upright support walls. Although restraining the cargo against the upright support walls of the container can be effective, the shifting forces that continue to act upon the cargo can cause the ropes or straps to break which in turn, results in unrestrained movement of the cargo within the cargo container.
Another means of eliminating movement of cargo is to strategically place each cargo item onto the floor of the cargo container in a manner to eliminate any empty cargo space thereabout. Now, as shifting forces act upon the cargo, the cargo is unable to move because the upright support walls of the cargo container and the sides of the cargo interact to restrain any movement of the strategically placed cargo items. For less-than-truckload amounts of cargo, this means is useless. Furthermore, eliminating any empty cargo space is not often conducive to efficient multiple deliveries of portions of the cargo.
Even with a sufficient amount of cargo being delivered to a single destination, it is not always possible to eliminate all empty cargo space due to the type of cargo being transported. To resolve this problem, space filling devices such as empty boxes or blankets can be used to fill the empty cargo space. However, if the cargo is sufficiently heavy, empty boxes can potentially be crushed when the cargo moves, thereby rendering the empty boxes useless for cargo restraint. Furthermore, a significant amount of empty cargo space to be filled makes empty boxes and blankets impractical for use.
Specific types of cargo pose even more challenging problems. For example, packaged beverage cans are extremely heavy and are typically loaded over the axles of a semi-trailer in order to evenly distribute the heavy weight appropriately thereabout. This loading arrangement often creates empty cargo space not only between the cargo and the upright support walls of the cargo container but also between cargo items. To maximize the load carrying capacity of the truck, usually the packaged beverage cans are stacked one on top of another within the cargo container close to the ceiling. Now, the shifting forces which are incurred during transportation can not only move the packaged beverage cans about the floor of the cargo container but also tip the upper packaged beverage cans over and into the empty cargo space. To eliminate this problem, a space filling structure is employed inside the cargo container. This space filling structure includes metal bars and rails which support sheets of plywood which, in turn, secure the cargo against moving and tipping. Although this space filling structure does effectively restrain the cargo, it is attendant with disadvantages. Such a space filling structure is permanent as it requires metal bars to be welded to the inside walls of the semi-trailer. Some commercial trucking companies refuse to make permanent modifications to the semi-trailers. Additionally, materials to construct this space filling structure and labor to install it are quite costly. Furthermore, this space filling structure is heavy and the weight added thereby reduces the cargo weight which can be hauled.
A need remains in the industry to provide a space-filling structure which is sufficiently versatile to fit into any size of empty cargo space between cargo items or between the cargo and the upright support walls of the cargo container. It would be advantageous if such a space filling structure can be folded or disassembled for compactness in order to stow it when not in use. It would also be advantageous if the space filling structure is lightweight and provides a high compressive strength to absorb and dissipate the compressive forces produced by the cargo. A need also exists to provide a portable space filling structure which not only prohibits movement of the cargo but also prevents tipping of the cargo. It would also be advantageous if the space filling structure can occupy significant volume in its working state but can occupy a minimum of volume in its stow state. The present invention addresses these needs and these advantages.